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SPF Record Builder

Build a valid SPF TXT record. Select your email providers, add custom includes and IP ranges, then copy the record into your DNS.

Email providers
Custom includes
Allowed IP ranges
Policy
DNS lookups0 / 10
Generated TXT record
v=spf1 ~all
Name: yourdomain.comType: TXTTTL: 3600
Add to DNS
yourdomain.com.  3600  IN  TXT  "v=spf1 ~all"

Related Tools

SPF Analyzer

Resolve and analyze the SPF record for any domain - including recursive include chains, DNS lookup counting, and policy violation detection.

DKIM Key Generator

Generate an RSA key pair for DKIM email signing. The public key goes into your DNS as a TXT record. Keep the private key on your mail server.

DMARC Generator

Build a valid DMARC TXT record for your domain. Choose a policy, add a reporting address, and copy the result into your DNS.

About this tool

SPF (Sender Policy Framework) tells receiving mail servers which IP addresses and mail services are authorized to send email for your domain. It is published as a DNS TXT record at your domain root. An SPF record that ends with -all rejects all mail from unlisted senders; ~all marks it as suspicious but still delivers it.

RFC 7208 limits SPF to 10 DNS-resolution mechanisms per lookup. Each include: counts as one lookup, but many providers have nested includes that expand further. If you exceed 10 lookups, SPF returns PermerFail and all messages appear unauthenticated. Use the SPF Analyzer to check an existing record's full resolution chain.